The Influence of Genotype, Priming Material, Temperature and Osmotic Potential of Priming Solution on Imbibition and Subsequent Germination of Sorghum and Pearl Millet Seeds During and After Treatment

Abstract

A setback in the physiological hardening or osmoconditioning of seeds (priming) is seed germination during treatment (premature germination). Ten genotypes of sorghum and pearl mil1et were screened for their tolerance to priming solution conditions and their subsequent premature germination at 23, 29 or 35°C. Priming in salt-based solutions gave lower premature germination percentages than in water (hardening) with the speed of germination increasing as priming temperature rose. Pusa 322, a pearl millet variety. was the most tolerant genotype. Generally, sorghum seeds were better adapted to treatments than those of pearl millet. Further experiments on imbibition of sorghum seeds showed that imbibition rates were higher in untreated than in primed seeds after periods greater than 24 hours of soaking and that a rise in priming temperature increased imbibition to a greater extent in the former.